Rounding machine and knife therefor



May 10, 1938. H. A. HAWKES ROUNDING MACHINE AND KNIFE THEREFOR Filed July 1, 1936 Patented May 10, 1938 PATENT QFFICE ROUNDING MACHINE AND KNIFE THERE- FOR Harry A. Hawkes, Chelsea, Mass, assignor to United Shoe Machinery Corporation, Paterson, N. J., a. corporation of New Jersey Application July 1, 1936, Serial No. 88,427

Claims.

This invention relates to machines by which sheet-material, such as stock for insoles of shoes,

is rounded or cut by a knife to correspond to the contour of a pattern.

In sole-rounding apparatus, of which the wellknown Planet machine disclosed in Letters Patent of the United States No. 882,009, Mayo, March 17, 1908, furnishes an example, relative movement produced between a knife and sheetmaterial held against a pattern causes workpieces to be formed by the knife under the guidance of the pattern. As the machine is constructed, it is entirely effective in its operation upon even thin stock when this is firm in character. But when it is soft and flaccid, as is certain insole-material, it tends to be displaced by the action of the knife and to Wave or chatter. This results in an objectionably rough, irregular edge upon the cut piece.

An object of the present invention is to obtain a cutting action which will give a smooth edge, even with thin, cheap stock. In the attainment of this object, a knife is employed which has a blade provided with an integral shank arranged to be secured in the holder of a rounding machine and a cutting edge extending from the shank to the opposite extremity of the blade, where it is provided with a projection entirely surrounding it and arranged for engagement with 30 the margin of the sheet-material being operated upon. With the knife in the machine, the margin-engaging surface of the projection extends along the work-contacting surface of the pattern and towardthe clamp by which the work-sheet is 35 held against said pattern. The projection bearing upon the work inside the cutting edge of the knife holds it firmly against displacement and insures a clean cut. Since it is desirable to obtain substantially uniform pressure of the pro- 40 jection against the work when the sheet differs in thickness, said projection is preferably in the form of a separate piece or block surrounding the blade and which has means for securing it in different positions along said blade. In the rounding machine, there is thus altered the relation of the work-engaging surface carried by the blade to the pattern and therefore to the material upon the pattern. To provide for the smooth movement of the block upon the work and the easy deflection of the chip cut by the knife, portions of the work-engaging surface and other portions of the block at the side toward the work are inclined or relieved.

In the accompanying drawing,

Fig. 1 illustrates a particular form of the knife of this invention, while Fig. 2 shows the knife in place in the rounding machine.

In the Planet rounding machine, the relative cutting movement between a knife l0 and a pattern 62, upon which a sheet of stock S is held by a clamp H, is effected by the travel of the knife, the pattern and clamp being stationary during the rounding operation. This travel is '10 imparted to the knife from a rotary table it, upon which is mounted for oscillation and bodily movement a carrier-arm 18 having on its inner extremity adjacent to the periphery of the pattern a holder 20. In this holder the shank 22 of 15 the knife H] is secured with the cutting edge 24 in a substantially vertical position, the shankportion of its flat inner side 26 being guided in its travel by contact with the periphery of the pattern. The blade of the knife is provided with 20 a projection extending from it above the pattern. The projection is preferably furnished by a block 28 having extending between its lower face 36 and upper face 32 a passage 34 to receive the knife-blade. The contour of this passage in a 25 horizontal plane may generally correspond to that of the blade, and the block is shown as secured variably in position upon the bladeby sct-screws 36. The surface extends laterally from the blade above and substantially parallel 30 to the upper face of the pattern, and consequently to the sheet S clalnped thereon, toward the clamp l4. There is also preferably an extension of the surface over the sheet and pattern along the line of the cut forwardly and rearward- 35 ly from the edge 24 and at the outer side of the blade opposite the surface 26. For a particular thickness of stock to be operated upon, the block 28 is adjust-able vertically upon the blade and secured thereon by the set-screws 36. face 30 bears upon the upper face of the sheet, holding it positively against upward displacement from the pattern as the knife passes through it. Moreover, the forward and rearward extension of the surface 38 has an ironing effect upon the upper face of the work, tending to free it from irregularities, either present in the stock or which might be produced in cutting. As a result of this, the edge and margin of the cut piece, even with relatively soft, sleazy material, is left uniformly even and smooth. The work-engaging portion of the surface 30 in advance of the edge 24 of the blade is shown as curved or inclined upwardly at 38 from the plane of the work. This furnishes a throat by which the upper surface of the work- The sur- 40 sheet is received during the travel of the knife and is prevented from catching. The outer edge of the surface at 40 is similarly curved or inclined to provide clearance for the chip which is cut, as this curves outwardly and upwardly.

Having described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. In a knife for use in rounding machines, a blade integral with a shank arranged to be secured in the. holder of the machine, said blade being provided with a cutting edge extending from the shank to the opposite extremity of the knife, a gage-block surrounding the blade and variable in position longitudinally thereof, and means carried by the block for securing it to the blade.

2. In a knife for rounding machines, a cutting blade, and a block secured to and supported wholly by the blade and provided at the side toward the work with a surface surrounding the blade, said surface being inclined in advance of the cutting edge and at the side of the blade opposite the work outwardly from the plane of said work.

3. In a rounding machine, a pattern furnishing a support for a work-piece, a clamp movable toward and from the pattern for securing the work-piece thereon, there being a portion of the work-piece extending over the pattern beyond the periphery of the clamp, a holder movable about the pattern, and a knife secured in the holder and extending above the pattern, said knife being provided with a projection extending over the pattern and toward the clamp and having a surface for engagement with the outer portion of the free margin of the work-piece which is substantially parallel to the upper face of the pattern and contacting with the outer portion of the free margin of the work-piece.

4. In a rounding machine, a pattern furnishing a support for a work-piece, a clamp movable toward and from the pattern for securing the workpiece thereon, there being a portion of the workpiece extending over the pattern beyond the periphery of the clamp, a holder movable about the pattern, a knife secured in the holder and extending above the pattern, said knife being provided with a projection extending over the pattern toward the clamp and contacting with the outer portion of the free margin of the workpiece, and means arranged to vary the position of the projection upon the knife.

5. In a rounding machine, a pattern and a clamp between which the work is held, a carrier and a knife mounted therein and movable about the pattern, a block surrounding the knife and provided with a work-engaging surface, and means arranged to secure the block in different positions upon the knife toward and from the pattern.

HARRY A. HAWKES. 

